Choosing between Monday Swimwear and Summersalt usually comes down to one question: what does your body need more, a top built for your exact cup size, or a suit that runs from a size 0 to a 24 with a torso length that actually fits you? That single decision separates these two brands more cleanly than price, fabric, or sustainability, all of which land closer than you might expect.
Both are direct-to-consumer swim labels with loyal followings and recycled fabrics. But they solve different problems. Monday, founded in 2014 by Natasha Oakley and Devin Brugman, builds its tops to fit each cup size individually rather than grading up from a small. Summersalt, launched in 2017, designed its fit around 1.5 million body measurements from 10,000 women and offers the widest numerical size range of the two. Here’s how they stack up, category by category, with an honest winner called each time.
Quick verdict
Choose Summersalt if you want the broadest size range (0–24), classic and long-torso length options, and lower prices, roughly $95 to $125 per suit.
Choose Monday Swimwear if you have a fuller bust or a small-band, large-cup shape, want underwire options, or you’re after elevated resort styling for a vacation wardrobe.
Neither wins outright. They serve different bodies and different occasions.
At a glance
| Monday Swimwear | Summersalt | |
|---|---|---|
| Typical price | Tops ~$96–$113; one-pieces ~$132–$189 | Most suits ~$95–$125 |
| Size range | P–VVV (petite through extended), cups A–E/F, some G | 0–24, classic and long-torso lengths |
| Fit approach | Tops fitted per cup size; underwire on select styles | Data-backed fit from 1.5M measurements; compression fabric |
| Fabric | 82% recycled nylon / 18% spandex (varies by style) | Recycled polyamide blends (e.g., 78% recycled polyamide) |
| Best for | Full bust, resort styling, adjustable support | Size inclusivity, long torsos, value |
| Founded | 2014 | 2017 |
Fit and sizing
Winner: Monday Swimwear (for bust range), Summersalt (for length range). This is a split decision, and it’s the most important one in the whole comparison.
Monday’s whole reason for existing is bust fit. Its tops are cut and manufactured for each cup size rather than scaled up from a small, which is how most of the industry works. The range covers roughly A through E/F cups, with some styles going to a G, and its sizing runs from Petite (P) through S, M, L, and the extended V, VV, and VVV bands. Co-founder Devin Brugman is an E/F cup herself, and reviewers who wear D+ sizes consistently single out Monday as one of the few brands that actually accommodates a small band with a large cup. As Marie Claire UK put it, Monday is one of the few brands that “prioritises fit above all else.”
Summersalt approaches fit from a different angle. Rather than cup-specific tops, it built its patterns around 1.5 million measurements collected from 10,000 women, then added compression fabric and, on many styles, built-in shelf bras. The standout feature is length: most suits come in both classic and long-torso options, which solves a fit problem that fuller-bust brands often ignore. If a one-piece has ever fit your bust but pulled too short in the body, this is the brand built for you.
So the honest answer depends on your shape. Small band, large cup, you’ll likely fit Monday better. Longer torso or a straightforward bust with a proportional body, Summersalt’s length options are hard to beat. Both brands lean heavily on adjustable straps and ties, so fine-tuning is possible either way. If you’re unsure where you land, Monday’s fit guide breaks coverage and support down style by style.
Size inclusivity
Winner: Summersalt. On pure range, this isn’t close.
Summersalt offers 0 through 24 across its swim line, and it was designed that way from the start using measurements from a genuinely diverse group of bodies. When Yahoo’s shopping editors tested swimwear across more than 20 women aged 24 to 71 and sizes 0 to 18, Summersalt was one of the top performers. The classic-plus-long-torso structure means the inclusivity is about proportion, not just circumference.
Monday’s extended sizing (up to VVV) is real and meaningful, especially for bust range, but the numerical span is narrower than Summersalt’s 0–24. Monday’s strength is depth within the bust dimension rather than breadth across the full size spectrum. If your primary need is a wide numerical range with plus sizes designed rather than adapted, Summersalt is the clearer fit.
Fabric and quality
Winner: Tie. Both use recycled fabrics and earn strong quality marks, with a slight difference in feel.
Monday’s suits are typically 82% recycled nylon and 18% spandex, with a structured, supportive hand that suits its bust-first design. The removable cups, gold hardware, and adjustable ties read as elevated rather than sporty. Reviewers note the fabric feels substantial, which matters for support.
Summersalt leans on a compression fabric it describes as several times stronger than standard swim material, built from recycled polyamide blends (one bestselling style is 78% recycled polyamide, 22% elastane). Yahoo’s reviewers praised the durability and “great tummy control,” and noted the suits “last multiple seasons.” That compression is central to how Summersalt delivers support without underwire.
Different philosophies, comparable results. Monday feels structured and resort-luxe; Summersalt feels firm and sporty-smooth. Neither is a quality compromise.
Styles and coverage
Winner: Monday Swimwear (for resort styling), Summersalt (for everyday versatility).
Monday reads like a vacation wardrobe. Alongside bikinis and one-pieces, it carries cover-ups, sarongs, linen sets, and knitwear, with a neutral, destination-ready palette and crinkle, rib, and geo textures. Underwire styles like the Sorrento top and the Honolulu one-piece give structured support that the compression-only approach can’t fully replicate for larger busts. If you’re packing for a resort trip and want the swim-to-dinner pieces to match, Monday is built for that.
Summersalt keeps a tighter catalog, around 20 core swim styles, and focuses on versatile silhouettes: the Sidestroke one-shoulder one-piece, wrap suits, high-waisted bottoms, and ruffle details. Coverage skews moderate to full, which pairs well with the compression fabric. It’s less of a full resort ecosystem and more a focused, do-it-well swim line.
Price and value
Winner: Summersalt. For most shoppers, this is the budget-friendlier brand.
Summersalt suits mostly land between about $95 and $125, and separates can come in lower. For a full one-piece with compression fabric and long-torso options, that’s competitive.
Monday’s tops run roughly $96 to $113 and one-pieces roughly $132 to $189 at full price, though frequent sales bring individual pieces well below that. Buying a bikini as a top-and-bottom set pushes Monday’s per-outfit cost above a comparable Summersalt one-piece. You are paying for cup-specific construction and resort styling, which is worth it if bust fit is your priority, but Summersalt delivers more suit for the dollar on average.
Sustainability
Winner: Tie, with an edge to disclosure. Both build swimwear from recycled materials.
Monday uses recycled nylon across much of its line and supports several charitable organizations. Summersalt uses recycled materials in its suits and packaging, and it’s one of the few swim brands with an independent third-party sustainability score: Good On You rates it “It’s a start,” with a Planet score of 3 out of 5. That external rating gives Summersalt a small transparency edge, though neither brand is a dedicated sustainability label. If verified sourcing matters to you, Summersalt’s public rating is the more checkable claim.
Shipping and returns
Winner: Summersalt. The return policy is friendlier, especially in the US.
Summersalt offers free shipping on US orders of $95 and up, plus free returns and exchanges for US customers. That removes most of the fit-anxiety risk of buying swim online.
Monday accepts US returns within 14 days for a refund, store credit, or a one-time exchange, but charges a returns processing fee of 4% (capped at $18) on refunds and doesn’t refund shipping. International customers get refunds only, with no exchanges. It’s a reasonable policy, but the fees and the exchange limits make it less forgiving than Summersalt’s free US returns, worth factoring in if you expect to try a couple of sizes.
Who should choose each
Choose Monday Swimwear if you:
- Have a fuller bust or a small-band, large-cup shape
- Want underwire or structured support, not just compression
- Are building a resort or vacation wardrobe with matching cover-ups
- Prioritize cup-specific fit over a wide numerical size range
Choose Summersalt if you:
- Want the broadest size range, 0 through 24
- Need long-torso length options
- Prefer a lower average price
- Value free US returns and an independent sustainability rating
The balanced verdict
These brands aren’t really competing for the same shopper. Summersalt wins on size inclusivity, price, and returns, and it’s the safer bet for most bodies looking for a well-made, versatile suit at a fair price with a generous return window. Monday wins on bust range, structured support, and resort styling, and it’s the clear choice if you’ve spent years failing to find a top that fits a fuller cup. Both use recycled fabrics, and both hold up over multiple seasons.
If your fit challenge is your bust, start with Monday. If it’s your torso length, your budget, or a plus size the brand actually designed for, start with Summersalt. And if you want to see how coverage and support break down before you commit, Monday’s fit resources are a good place to begin.
Editorial buying guide. Prices, sizing, and availability change over time; confirm current details on each brand's site before purchasing.
